During the installation of ubuntu from a USB key to a USB SSD, the bootloader was unintentionally placed on my laptop's internal Win10 drive. With the external SSD unplugged, Windows still booted OK - but the EFI boot menu only showed the "ubuntu" option.
I removed the inappropriate "ubuntu" listing from the boot menu by following steps from How do I remove "Ubuntu" in the bios boot menu? (UEFI) (removing the EFI entry with efibootmgr and deleting the ubuntu folder from the EFI partition), however the "Windows Boot Manager" entry is still missing from the boot menu, even though it is present in the EFI entries (see below). My BIOS does not have facilities to manually add boot entries, and it does not correct itself after successfully booting to Windows...
I have read the manual pages for efibootloader but I don't see anything obviously wrong, and I'm a little leery of messing with this without guidance. Can anyone help me figure out how to restore the Windows entry properly?
Output from efibootmgr (as viewed from the original LiveUSB key):
BootCurrent: 2001
Timeout: 2 seconds
BootOrder: 0004,0003,2001,2002,2006,2004,2005,0002,0000,0001,3001
Boot0000 Boot Device List
Boot0001 Diagnostic Menu
Boot0002 UiApp
Boot0003* HDD/SSD
Boot0004* Windows Boot Manager
Boot2001* USB Memory
Boot2002* USB ODD
Boot2004* LAN1
Boot2005* LAN2
Boot2006* FDD
Boot3001 HDD Recovery